From 84a0950aeafd4a17e8dc8b5b04e0c82f88eb08ae Mon Sep 17 00:00:00 2001
From: Garance A Drosehn <gad@FreeBSD.org>
Date: Tue, 28 Jan 2003 01:21:57 +0000
Subject: [PATCH] Changes so the 'pw' command will allow '$' as the last
 character in a userid or group name (mainly for the benefit of samba).  This
 pretty much rewrites he pw_checkname() routine, but should work exactly the
 same except for the above change, and that error messages are somewhat more
 informative.

PR:		28733 46890
Inspired by:	example patch written by Terry Lambert
Reviewed by:	no objections on freebsd-arch and freebsd-current
MFC plans:	no plans, but will do if people want it in stable.
---
 usr.sbin/pw/pw_user.c | 63 ++++++++++++++++++++++++++++++++++---------
 1 file changed, 50 insertions(+), 13 deletions(-)

diff --git a/usr.sbin/pw/pw_user.c b/usr.sbin/pw/pw_user.c
index 456c954d21fe..a2d5e78dbbd5 100644
--- a/usr.sbin/pw/pw_user.c
+++ b/usr.sbin/pw/pw_user.c
@@ -1194,21 +1194,58 @@ print_user(struct passwd * pwd, int pretty, int v7)
 char    *
 pw_checkname(u_char *name, int gecos)
 {
-	int             l = 0;
-	char const     *notch = gecos ? ":!@" : " ,\t:+&#%$^()!@~*?<>=|\\/\"";
+	char showch[8];
+	u_char const *badchars, *ch, *showtype;
+	int reject;
 
-	while (name[l]) {
-		if (strchr(notch, name[l]) != NULL || name[l] < ' ' || name[l] == 127 ||
-			(!gecos && l==0 && name[l] == '-') ||	/* leading '-' */
-			(!gecos && name[l] & 0x80))	/* 8-bit */
-			errx(EX_DATAERR, (name[l] >= ' ' && name[l] < 127)
-					    ? "invalid character `%c' in field"
-					    : "invalid character 0x%02x in field",
-					    name[l]);
-		++l;
+	ch = name;
+	reject = 0;
+	if (gecos) {
+		/* See if the name is valid as a gecos (comment) field. */
+		badchars = ":!@";
+		showtype = "gecos field";
+	} else {
+		/* See if the name is valid as a userid or group. */
+		badchars = " ,\t:+&#%$^()!@~*?<>=|\\/\"";
+		showtype = "userid/group name";
+		/* Userids and groups can not have a leading '-'. */
+		if (*ch == '-')
+			reject = 1;
 	}
-	if (!gecos && l > LOGNAMESIZE)
-		errx(EX_DATAERR, "name too long `%s'", name);
+	if (!reject) {
+		while (*ch) {
+			if (strchr(badchars, *ch) != NULL || *ch < ' ' ||
+			    *ch == 127) {
+				reject = 1;
+				break;
+			}
+			/* 8-bit characters are only allowed in GECOS fields */
+			if (!gecos && (*ch & 0x80)) {
+				reject = 1;
+				break;
+			}
+			ch++;
+		}
+	}
+	/*
+	 * A `$' is allowed as the final character for userids and groups,
+	 * mainly for the benefit of samba.
+	 */
+	if (reject && !gecos) {
+		if (*ch == '$' && *(ch + 1) == '\0') {
+			reject = 0;
+			ch++;
+		}
+	}
+	if (reject) {
+		snprintf(showch, sizeof(showch), (*ch >= ' ' && *ch < 127)
+		    ? "`%c'" : "0x%02x", *ch);
+		errx(EX_DATAERR, "invalid character %s at position %d in %s",
+		    showch, (ch - name), showtype);
+	}
+	if (!gecos && (ch - name) > LOGNAMESIZE)
+		errx(EX_DATAERR, "name too long `%s' (max is %d)", name,
+		    LOGNAMESIZE);
 	return (char *)name;
 }